Insulated water-cooled furnace supporting structure



July 4, 1967 T. P. GREANEY INSULATED WATER-COOLED FURNACE SUPPORTINGSTRUCTURE Filed March 30, 1965 Flt 1- A. c, T n. r t n.

min H 1 i n T t I u. i, 1 I

INVENTOR. 5 THOMAS P. GREA/VEY A) forney United States Patent Office3,329,414 Patented July 4, 1967 3,329,414 INSULATED WATER-COOLED FURNACESUPPORTING STRUCTURE Thomas P. Greaney, Hammond, Ind., assignor toUnited States Steel Corporation, a corporation of Delaware Filed Mar.30, 1965, Ser. No. 443,942 13 Claims. (Cl. 2636) This invention relatesto an insulated water-cooled furnace supporting structure and moreparticularly to such structures for supporting steel slabs or billetswhich are being heated prior to rolling. In a conventional continuousreheating furnace, the slab to be heated is pushed through the furnaceon water-cooled skids which extend longitudinally through the furnaceand are supported on transversely positioned pipes, which in turn aresupported by vertical pipes. The pipes must be insulated to prevent themfrom absorbing heat. Prior to my invention this was usually done eitherby applying preformed refractory sleeves or by applying the insulationin plastic form around the pipes. In most cases metallic mesh was usedas a reinforcement for the insulation. Typical insulations are shown inSchmidt Patent No. 2,436,452 dated February 24, 1948, and Brough et al.Patent No. 3,149,826 dated September 22, 1964. The metallic mesh acts asa heat conductor to the pipes, thus decreasing its effectiveness. Alsowhen the insulation becomes hot it becomes brittle and cracks as theweight of the slab causes the skids to flex. Thus, maintenance andrepair costs were high.

It is therefore an object of my invention to provide an insulated,water-cooled furnace supporting structure which includes means forpreventing or limiting cracking of the insulation.

Another object is to provide such a structure in which metallicreinforcement is eliminated.

These and other objects will be more apparent after referring to thefollowing specification and attached drawings, in which:

FIGURE 1 is a plan view of the structure of my invention;

FIGURE 2 is an enlarged elevation of a portion of FIGURE 1;

FIGURE 3 is a sectional view taken on the line IIIIII of FIGURE 2;

FIGURE 4 is a sectional view taken on the line IVIV of FIGURE 1; and

FIGURE 5 is a view, similar to FIGURE 3, showing another embodiment ofmy invention.

Referring more particularly to the drawings, reference numeral 2indicates a horizontal tube for receiving cooling water. A longitudinalskid bar 4 is welded to or otherwise attached to the top of the tube 2.Tube 2 and bar 4 are arranged longitudinally of the furnace, not shown,and are supported by a transverse tube 6 therebeneath. The tube 2 has aplurality of longitudinally extending lugs 8 welded thereto ondiametrically opposite sides thereof. The tube 2 is surrounded by a heatbarrier 10 which includes a plurality of spaced apart sets of lightweight insulating members 12 and a compressible washer 14 betweenadjacent sets of members 12. There are two members 12 in each set witheach member extending around approximately one half the circumference ofthe tube 2 and being provided with slots 16 for receiving the lugs 8.The members 12 abut each other at their lower ends with a hightemperature cement mortar 18 holding them together. The top of themembers 12 are flattened out so that they are below the top of the bar4. A high temperature air setting mortar 20 is provided between the tube2 and members 12. A similar air setting cement 22 covers the outside ofthe members 12 and gives longer life thereto. The members 12 are made ofa high temperature insulating firebrick such as Insolite. This is alight weight, porous fireclay material well known to those skilled inthe art. Insolite weighs approximately 48 lbs. per cu. ft. The washers14 are made of a refractory insulation material which is compressibleunder temperature. It is preferred to use an alumina silica materialwhich is melted and then blown with an air or steam jet to produce afibrous material such as Fiberfrax or Kaowool. While the length of themembers 12 may vary it is preferred to have them approximately 9 in.long. I have found that the use of the washers 14 prevents or greatlyreduces breakage of the members 12 which would otherwise occur due tothe flexing action of the pipe 2.

Barrier 24 used with tube 6 is the same as barrier 10 except that itsinsulating members 26 are not cut away at the top thereof.

In the embodiment of FIGURE 5 pointed radial lugs 28 are used in placeof the lugs 8 and a barrier 30 is provided which is identical to barrier10 except that the slots 16 are omitted from insulating members 32.Because of the texture of the high temperature insulating firebrick themember 32 may be pressed onto the sharp v lugs 28.

The present invention reduces repair and maintenance costs, adds to theefliciency of the furnace and the quality of the product due to betterinsulation, and is much cheaper to install. In a typical installationthe insulation cost is $5 per lineal ft. as compared to a cost of $12per lineal ft. for conventional installations.

While several embodiments of my invention have been shown and describedit will be apparent that other adaptations and modifications may be madewithout departing from the scope of the following claims.

I claim:

1. An insulated water-cooled furnace supporting structure comprising atube for receiving water, a plurality of spaced apart sets of insulatingmembers surrounding said tube, each of said insulating members extendingaround less than the full circumference of said tube, and a compressiblewasher in the space between adjacent sets of insulating members.

2. An insulated water-cooled furnace supporting structure according toclaim 1 including a high temperature air setting mortar between saidtube and insulating members and around the outside of said insulatingmembers.

3. An insulated water-cooled furnace supporting structure according toclaim 1 in which the insulating members are made of porous fireclay andthe washers are made of porous alumina silica.

4. An insulated water-cooled furnace supporting structure according toclaim 3 including a high temperature air setting mortar between saidtube and insulating members and around the outside of said insulatingmembers.

5. An insulated water-cooled furnace supporting structure comprising atube for receiving water, a plurality of longitudinally extending lugsattached to and extending outwardly from said tube on diametricallyopposite sides thereof, a plurality of spaced apart sets of insulatingmembers surrounding said tube and supported on said lugs, each of themembers in each set extending around approximately one half thecircumference of said tube, and a compressible washer in the spacebetween adjacent sets of insulating members.

6. An insulated water-cooled furnace supporting structure comprising atube for receiving water, a plurality of longitudinally extending lugsattached to and extending outwardly from said tube on diametricallyopposite sides of said tube, a plurality of spaced apart sets ofinsulating members surrounding said tube and supported on said lugs,each'of the members in each set extending around approximately one halfthe circumference of said tube, said insulating members being made ofporous fireclay, air setting mortar between said tube and insulatingmembers and around the outside of said insulating members and betweenthemembers of each set, and a compressible washer in the space betweenadjacent sets of insulating members, said washers being made of porousalumina silica.

7. An insulated water-cooled furnace supporting structure comprising ahorizontal tube for receiving water, a longitudinal bar attached to thetop of said tube, a plurality of spaced apart sets of insulating memberssurrounding said tube, each of the members in each set extending aroundapproximately one half the circumference of said tube and abutting eachother at the bottom thereof and abutting said bar at the top thereofwith the top of the members being below the top of the bar, and acompressible washer in the space between adjacent sets of insulatingmembers.

8. An insulated water-cooled furnace supporting structure according toclaim 7 including a high temperature air setting mortar between saidtube and insulating members and around the outside of said insulatingmembers.

9. An insulated water-cooled furnace supporting structure according toclaim 7 in which the insulating members are made of porous fireclay andthe washers are made of porous alumina silica.

10. An insulated water-cooled furnace supporting structure according toclaim 7 including a plurality of longitudinally extending pointed radiallugs attached to and extending outwardly from said tube on diametricallyopposite sides of said tube for supporting said members.

11. An insulated water-cooled furnace supporting structure according toclaim 10 including a high temperature air setting mortar between saidtube and insulating members and around the outside of said insulatingmembers.

12. An insulated water-cooled furnace supporting structure according toclaim 10 in which the insulating members are made of porous fireclay andthe washers are made of porous alumina silica.

13. An insulated water-cooled furnace supporting structure according toclaim 12 including a high temperature air setting mortar between saidtube and insulating members and around the outside of said insulatingmembers.

References Cited UNITED STATES PATENTS- 2,435,362 2/1948 Morton 236-62,482,878 9/1949 Schmidt 263-6 2,707,095 4/1955 Parsons et al. 138-149 X2,884,879 5/1959 Corriston 263-6 3,169,754 2/1965 OReilly 263-63,226,101 12/1965 Balaz et al. 263-6 FREDERICK L. MATTESON, ]R., PrimaryExaminer.

JOHN J. CAMBY, Examiner.

1. AN INSULATED WATER-COOLED FURNACE SUPPORTING STRUCTURE COMPRISING ATUBE FOR RECEIVING WATER, A PLURALITY OF SPACED APART SETS OF INSULATINGMEMBERS SURROUNDING SAID TUBE, EACH OF SAID INSULATING MEMBERS EXTENDINGAROUND LESS THAN THE FULL CIRCUMFERENCE OF SAID TUBE, AND